A Steak in Genomics™

 Jamie Courter and Jared Decker had the opportunity to present a webinar on hair shedding with the American Angus Association. Watch below! Didn't get your question answered? Be sure to check out our presentation at the Beef Improvement Federation Symposium on June 11th, 2024 at 3 pm. 

       For those who have been scrolling through social media and various agriculture-based news outlets in the past 12 to 18 months, it may seem as though there has been quite a few “new” genetic mutations or defects that have been identified. For most producers this is something they have dealt with before. But for others this may be the first time they are being faced with what seems like a “sky is falling” predicament. Regardless of which group you belong to, understanding what genetic mutations are, how they happen, and what to do when they are identified may prove helpful for the future.      To put this into perspective, cattle have 30 pairs of chromosomes. They inherit one of each pair from their sire and the other from their dam. A typical cattle genome consists of 2.7 billion nucleotides (A, T, G, C), or pieces of DNA, each occurring again in a pair. When they come together to form a fertilized egg, or future fetus, that is 5.4 billion nucleotides that are replicated each tim

The tool is part of a study published in an Oxford University Press journal and could be used to help cattle farmers improve the health, well-being and productivity of their herds.   A groundbreaking, newly-published study by CAFNR researcher Jared Decker uses genomics and citizen science to help cattle farmers and ranchers across the globe make better breeding selections that will ultimately improve sustainability, animal welfare and profitability of their operations. And, the key to all of this? Hair shedding. “This project has been really exciting to me because it blends both very basic research all the way to very applied research, so it is one of those rare projects that covers that wide spectrum,” said Jared Decker, associate professor of animal sciences and Wurdack Chair of Animal Genomics. According to Decker, some cows shed their winter hair more effectively than others. This means that some lose their heavy winter coats during the spring months before the heat of summer sets

 We have all heard the saying “You can’t judge a book by its cover”, but it is true that the cover is what initially draws a person to pick up the book in the first place. The same is true with selecting and breeding cattle. What the animal looks like matters. However, what the saying really means is it’s what is inside the book, or in this case underneath the animal’s hide, that adds the most value. The importance of phenotypic selection in cattle is non-negotiable. But, once someone has made that initial gate cut, genomics can help in marketing the value of sale bulls and heifers with increased confidence. Cattlemen and women do their best to select elite bulls to mate their cows to. Unfortunately, basic biology reminds us that variability exists even within the best mating plans. But exactly how much variability? Well, while discussed at length in the extension article The Random Shuffle of Genes: Putting the E in EPD , basic math tells us that within a single full sibling matin

In the last blog post, I defined Expected Progeny Differences (EPDs), the accuracy of said EPD, and the percentile rank. An EPD is an estimate of the genetic merit an animal will pass on to its progeny, on average. They can be used to sort animals according to their potential to make genetic change within a herd, or when making bull buying decisions. A percentile rank simply reports where the specific EPD for that animal ranks across the entire breed from 1 (top) to 100 (bottom). While I touched on the value of genomics and how it increases accuracy, to do that justice really takes a separate post – so here goes. Remember, EPD stands for ‘Expected’ Progeny Difference. In other words, it is the evaluation’s best assortation of an animal’s genetic merit based on the information available at the time. Traditionally, that would be the animal’s (assumed) pedigree, phenotype data, and progeny information. In the case of young sires, sometimes that can be limited simply due to their age.

As a dry 2023 ends, with hopefully a little more moisture, and we enter spring bull buying season, it is imperative that producers arm themselves with information to make educated purchasing decisions. As you continue to flip through various catalogs, selecting bulls as you have so many times before, I would like to take this opportunity to provide what I believe are fundamental pieces of information to better assist a producer in their bull buying decisions.  In addition to overall soundness and conformation of a bull, it is always important to select a sire who is ‘backed by data’. You wouldn’t necessarily go out and buy a new pickup truck without researching its horsepower, torque, and overall tow-rating. Instead, you would ensure that the overall mechanics of the engine matched your daily needs. The same should be true about purchasing a new herd bull or AI sire. Instead of an owner’s manual you now have EPDs. Figure 1. Sources of information used to calculate an Expected Progeny

  When we think about DNA testing in cattle, we often revert to more complex testing like “GGP 50 or 100K” or “HD50K” and precise predictions of progeny performance in the form of genomically enhanced expected progeny differences (GE-EPD). What we often overlook is the fact that with every SNP panel that is purchased for an animal, parentage information is included at no additional cost. It’s one of the unsung heroes of genomic technology. Let’s talk about why. Did you know that on average 10% of parentage is misreported to breed associations? Of course, this isn’t on purpose but rather a result of animals being sired by cover bulls instead of AI sires and other such cases. Just last year I had a parentage issue where a cow was AI’d and put in a pasture with a cover bull after a short waiting period but ended up being bred by another cover bull in between both exposures. Anything is possible. For seedstock producers, a lot rests on the pedigree of an animal. When you open a sale ca